Abstract:
Most water supply services of cities in Ethiopia are unreliable, particularly in providing an
adequate amount. The reasons could be diverse and many, but the most common factors are a
lack of proper operation and maintenance (O&M), and poor asset management practices of the
distribution systems. These bottlenecks of service provisions have significantly influenced the
overall progress of the national development, in particular, the lives of citizens. Therefore, this
study aimed at alleviating water distribution related problems through providing Geographical
Information System (GIS) based Decision Support System (DSS) to systematize the existing
O&M method for sustainable water distribution in the Harar city. To achieve this duty, None
Revenue Water (NRW) of the Harar city was analyzed using International Water Audit (IWA)
method. The pipe burst rate was analyzed using excel sheet based on pipe burst history data as
well. Pipe risk assessment was performed based on a new approach called T-MALDP tactic,
using GIS 9.3 Index modeling. Sensitivity analysis was carried out for comparison. The
hydraulic characteristic of the distribution system was simulated via Epanet. Database was
prepared and suggested DSS for the water distribution O&M process. From the analysis, the
NRW result, 45.27% and the burst rate 6.18/km/annum was indicated poor asset management
practice. The T-MALDP pipe risk analysis result indicates 18%, imperative, 17% Desirable,
28% required monitoring and 37% no need of improvement, which map was displayed with a
premium Google Earth image of the Harar town. The sensitivity of T-MALDP risk result was
measured with statistical measures and map removal technique. Hence, pipe diameter imposed
the highest impact on pipe vulnerability to burst followed by pipe material, pressure and traffic
loading. Moreover, few significant correlations between T-MALDP parameters were found
independently. Map removal sensitivity analysis was indicated that as the amount of pipe
failure factors increase, the chance of getting the riskiest pipe will increase. The existing
distribution system was modified and optimized. Applying GIS and DSS in the proposed O&M
method will increase the efficiency and assist the water network management. The output of
the research showed that, in order to improve the efficiency of the Harar town water network
management, GIS, DSS and Hydraulic modeling based asset management is highly applicable.
